The subject invention relates to an apparatus for finishing the terminal end of a plastic optical fiber and ferrule of a connector assembly.
There are numerous patents on various optical fiber connector structures and method of making them. One quite common way is to form the connector structure independent of the fiber, inserting a connector and ferrule attached onto the fiber, and gluing the fiber in place. A basic problem with such an approach is that the location of the end of the coating on the fiber and the beginning of the ferrule when inserted into the connector, neither of which are visible, cannot be precisely determined. In many instances, an unsupported length of fiber exists between the end of the coating and the beginning of the ferrule. Such a structure is quite susceptible to failure as a result of the unsupported length of the optical fiber. Also, crimping is often used to hold the structure together.
A further problem with the prior art devices is failure of the cable where it joins the connector body. The use of flexible strain relief is common but the prior art strain relief devices do not bond directly to the cable jacket. An adhesive compound is often used to affix the strain relief boot the cable jacket and connector body.
There is also a problem of diversity of connectors and the problems inherent with adapting a cable-ferrule combination that can be readily adapted to a multiplicity of different connectors.
As is known, finishing the terminal end of a connector assembly has heretofore been difficult because transverse cuts of the assembly material were difficult to accurately make and anomalies thousandths of an inch can be detrimental to performance.
Finishing of plastic optical fiber mounted in a connector has also been by hot plate or abrasive polishing. These methods have difficulty maintaining a flat surface. The quality of finish is dependent on operator skill and therefore is difficult to control.
The present invention is directed to overcome one or more of the heretofore problems, as set forth above.
In one aspect of the invention, an apparatus is provided for finishing the terminal end of a connector assembly having a ferrule fixedly connected to a plastic optical fiber. The apparatus has a frame, a motor, a holding member a drive member and a cutting element. The motor has an axis of rotation and is connected to the frame. The holding member has an axis substantially parallel to the motor axis and laterally spaced therefrom. The holding member is connected to the frame and adapted to releasably maintain the connector assembly coaxially positioned relative to said holding member. The drive member is connected to one of the motor and the holding member for movement of one toward the other along a pathway substantially parallel to the axis of the other. The cutting assembly has a diamond cutting element. The cutting assembly is axially connected to the motor. The diamond cutting element has a linear cutting edge of a length greater than the diameter of the terminal ends of the ferrule and optical fiber.
In another aspect of the invention, a method is provided for finishing the terminal end of a connector assembly having a metal ferrule fixedly connected to a plastic optical fiber. The connector assembly is maintained at a preselected axial position and orientation. A diamond having a cutting edge is passed through the ferrule and optical fiber. Preselected portions of the terminal end portion of the connector assembly are progressively sliced therefrom at an angle of 90 degrees relative to an axis of said ferrule and optical fiber. The slicing of the connector assembly is terminated at a preselected position.